Toggle press



Dec. 12, 1944.

F. J. RODE ETAL TOGGLE PRESS Filed Nov. 21, 1942 7 3 Sheets-Sheet l 00OOO Dec. 12, 1944- F. J. RODE ET AL TOGGLE PRESS Filed Nov. 21, 1942 3Sheets-Sheet 2 FIGZ.

ATTORNEYS.

1944- F. J. RODE ET AL 2,364,661

TOGGLE PRES S Filed Nov. 21, 1942 3 Sheets-Sheet 6 ATTORNEYS.

Patented Dec. 12, 1944 TOGGLE PRESS Fredrich J. Rode and Mi:

Brooklyn, N. Y., a corporation Ohio, assignors to edith R. Hatch,Toledo,

W. Bliss Company,

of Delaware 1 Application November 21, 1942, Serial No. 466,468

17 Claims.

This invention is directed to improvements in double action sheet metalpresses of the front to back type, i. e. of the type wherein the axes ofthe driving mechanisms for the main or die slide and the blank clampingslide extend from the front to the back of the crown of the press asdistinguished from presses wherein such mechanisms have axes extendingfrom side to side of the press.

Front to back presses have been built heretofore incorporating a geardriving system of pinions and bull gears drivingly extending to thecrank shaft of the press and with associated toggle mechanisms foroperating the clamping slide all arranged within the front and backbearing walls of the crown casting. While operatively satisfactory, theassembly and repair replacement problems of presses of large capacityand size detracted from the advantages otherwise presented by suchpresses ,over the side to side type of press. Wherefore the generalobject of the present invention is the provision of a novel arrangementof the elements of the die slide drive and the clamping slide drive sothat the toggle mechanism or mechanisms can be disposed on the outsideof the main crown structure while remaining in efilcient cooperativerelation to the die slide drive mechanism and whereby the fitt ng andassembly of the mechanical elements of the respective mechanisms can beeffected independently.

A further object of our invention is to overcome the disadvantages of acombined gear drive and toggle drive heretofore cooperatively grouped ina crowded interdependent manner between the front and back walls orbeams of the press crown structure.

A further object of the present invention is the provision of a novelarrangement of the toggle mechanisms of a front'to back double actionsheet metal press on the outside of the front and back beams or walls ofthe crown structure whereby the distance between these walls may besubstantially decreased over prior practices while permitting of adirect transmission of force to the press crank and the avoidance of thetransmission of the main torque load through the main crankshaftbearings of the crown structure.

Other features of our invention will appear to those skilled in the artfrom the following description which refers to the accompanying drawingsillustrating a preferred embodiment thereof.

I The essential'characteiistics of the invention are summarized in theclaims.

In said annexed drawings:

Fig. 1 is a front elevation of a sheet metal press embodying thefeatures of the invention;

Fig. 2 is a top view of the crown and associated mechanism as viewedwith the top cover, the clutch and brake removed;

Fig. 3 is a cross-sectional elevation taken in two planes as indicatedby the step back line 33 of Fi 2 and showing the crown, the die slideand the associated mechanisms for operating the die slide and workclamping slide; and

Fig. 4 is a cross-sectional elevation of the upper part of the crownstructure taken substantially along the line 4-4 of Fig. 1.

Referring more particularly to Fig. 1, the press will be seen tocomprise a base 6, spaced uprights mounted thereo and a crown 8supported by these uprights and provided with a removable cover 9 ontop. Extending through the base, uprights, and crown are tie-rods 5adapted to hold the above mentioned parts in place, and openings I 2 areprovided in the crown (see Fig. 2) through which the tie-rods pass andon top of which they are fastened by nuts (not shown).

Mounted within the press between the uprights 1 is a reciprocating blankclamping slide Ill guided during its movement in gibs H, which arebolted to the uprights.

The crown is provided with bearings for the drive shaft and supportsmost of the drive transmitting members. As already mentioned above,according to the novel arrangement of this invention an important partof the drive transmitting elements is disposed on the outside of themain crown structure, a feature which greatly improves accessibility tosuch parts of the press.

The drive mechanism which will now be described with reference to Figs.1, 2 and 4, comprises a flywheel l4 driven from a motor shaft l3 bymeans of an endless belt I5. The flywheel is mounted for idle rotationon a shaft l6 which is journalled in bearings ill of conventionaldesign, said bearings being secured to the crown as at IT. Keyed toshaft iii are a clutch l9 and a brake 20. The clutch shown is of thesingle plate dry disk type, but it will be understood that any otherconvenient clutch could be used as well.

On the other side of the flywheel I4, as shown in Fig. 4, the driveshaft has keyed thereon a pinion 23 which is in driving engagement witha gear 24. The hub of this gear is mounted on one end of a sleeve 25whose other end forms a pinion 26. Both end portions of sleeve 25 havinga cylindrical recess adapted to receive sleeveshaped bearings 21 and 28respectively, the balanoe of which is disposed within journaled portions30 of the crown.

Carried by bearings 21 and 2' and the portion of sleeve 25 extendingbetween said two bearings, is a shaft 29, which is one of the rockershafts on which one pair of toggle levers forming the drive for the dieslide are mounted. Shaft 29 extends from the front to the rear of thecrown and carries one of the above mentioned toggle levers at, each end,the front toggle lever being shown in Fig. 1 and designated by 3|.

The above mentioned pinion 26 is in engagement with a gear 33 mounted ona shaft 34 which is parallel to shaft 23 and forms the second rockershaft for supporting the other two toggle levers at its front and backend respectively. One of these toggle levers is shown and designated by35 in Fig. 1. Shaft 34 also carries two pinions 36 and 31 which drivetwo bull gears 38 and 3! respectively, which are mounted on a steppedportion ll of the main crankshaft 4| and drive the cheek ll of the crankshaft.

The crank shaft as shown in Fig. 3 is a stepped shaft, the main portionIII of which is journalled in sleeve bearings 42 carried by the crowncasting. The outermost stepped portion 43 serves to support a pivotallymounted crank 53 which is a driving connection to the toggle mechanismto be later described. The crank cheeks of the main crank are shown atll and the crank pin at 45, while 16 designates the eccentric strapwhose free end is connected to a pin 41 which is carried by a member I!forming part of the die slide 54.

The effective length of the die slide is capable of adjustment by anysuitable mechanism well known to the art such as that mechanismdiagrammatically shown at 58, which is operated by a motor 39. The motor9 drives the worm shaft 50a and the worm 50b disposed in meshingrelation with the worm wheel This wheel 5| is carried by a block 52which is in threaded engagement with the member 48. By this arrangementit is possible to lengthen or shorten the slide 54 as required.

Slide 5| is provided with an extension 55 which forms a circular troughfor receiving oil that may drip down from the bull gears and may bedrained at 55.

The arrangement of the toggle mechanism will now be described withreference to Figs. 1 and 3. As already mentioned the main crankshaft IIIis provided at each end with a stepped portion 43 for the mounting of asmall crank 53 that is linked at 5| to a connecting member 59 having itsfree end pivoted to a slide member 60. This member is mounted for up anddown movement in ways SI and, at its upper end, has pivotally connectedthereto links 2, 3 making connection with toggle members 3| and 35respectively.

These toggle levers are joumalled at their other ends to connecting rods65 and 66 which in turn are pivoted at their other ends to adjustmentscrews BI and 69 located within bosses II and 'Il formed on the outsideof slide II. The screws are arranged to cooperate with double lock nuts13, ll, respectively, which in their locking position abut on shouldersof the bosses II. For adjustment of the screws one of the lock nuts isloosened whereupon the other-may be turned, thereby making screw $3 moveup or down respectively and changing the stroke of the clamping slide togreater or smaller length as required.

It will be understood that the toggle mechanism comprises two toggles onthe front wall of the crown and two on the back wall, ,all of which workin unison, though they may be individually adjusted by the screw anddouble lock nut mechanism just described. The screw mechanism is used toadjust the clamping slide to the height of the die space, thus insuringa perfect cooperation between the respective parts of the double actionpress.

The operation of the press does not need any further explanation sinceit will be clearly understood from the foregoing description. It will belikewise understood that the novel arrangement of the toggle mechanismson the outside of the crown structure affords several advantages, themost important of which are accessibility of parts for assembly andrepair and compactness of crown structure owing to the fact that thecrown only houses the drive mechanism for the die slide between itswalls. Another advantage is the better distribution of torque load sincethe construction makes it possible to avoid the transmission torque ofthe main crank pin through the main crankshaft bearings of the crown.

Also, it will be apparent that the disclosed arrangement of the maincrank drive entirely within the crown walls and the toggle mechanismoutside of the crown walls permits of a very substantial reduction ofthe distance between the main crankshaft bearings, a feature which ishighly desirable in heavy press structure of the general type to whichthis invention pertains. This arrangement isconducive to compactness inthe entire design of the press and the operating parts can be enclosedconveniently without substantial increase in the cost of manufacturethereof.

Should one of the toggle mechanisms break down it is practical tooperate the press with. only one set of toggle mechanisms and in someclasses of production the press is equipped with only one toggle drivefrom the main crankshaft, in which instance the rocker shafts would beheavier than in the case of a double toggle drive arrangement operatingfrom each end of the main crankshaft. All toggle parts are accessiblewithout disruption of the gear train drive.

Itwill be apparent to those skilled in the art that the togglearrangement disclosed simplifies the obtaining of a uniform distributionof the four-point pressure application to the work clamping slide.

Other advantages will be apparent to those I skilled in the art and thedisclosure is not to be considered as a limitation of the inventionother than we have defined the same in the appended claims.

Other modes of applying the principle of our invention may be employedinstead of the one explained, change being made as regards the mechanismherein disclosed, provided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

We therefore particularly point out and distinctly claim as ourinvention:

1. In a sheet metal working press of the double action front to backtype the combination of a gear train arranged to drive a maincrankshaft, a die slide driven by the crankshaft, dual toggle mechanismfor operating the work clamping slide of the press including two rockershafts rotatably supporting members of said gear train, and meaninterconnecting said crankshaft and said rocker shafts for imparting arocking movement to said rocker shafts to thereby actuate said togglemechanism.

2. In a sheet metal working press of the double action front to backtype, the combination of a crown structure comprising a front and a backbeam, '12, main crankshaft Journalled in said beams, a gear traindisposed between said beams to drive the crankshaft, toggle mechanismdisposed to the front and rear of said beams respectively and adapted tooperate the work clamping slide of the press, said toggle mechanismsincluding rocker shafts extending through said front and back beams ofthe crown structure and serving to rotatably support certain of theclamping slide of the press, said toggle mechanisms including two rockershafts extending through said front and back beams of the crownstructure and serving to rotatably support certain of the members ofsaid gear train, and means including an auxiliary crank mounted at eachend of said main crankshaft, for imparting a rocking movement tosaidrocker shafts.

4. In a sheet metal working press of the double action front to backtype, the combination of a crown structure comprising a front and backbeam, a main crankshaft journalled in saidbeams, a gear train disposedbetween said beams to drive the crankshaft, dual toggle mechanismdisposed to the front and rear of said beams respectively and adapted tooperate the work clamping slide of the press, said toggle mechanismsincluding two rocker shafts extending through said front and back beamsof the crown the press, and having structure and serving to rotatablysupport certain of the members of said gear train, and means mounted onthe crankshaft but remote from the crank for imparting a rockingmovement to said rocker shafts.

5. A double action sheet metal press of the front to back gear andtoggle drive type having the gear train for driving the crankshaft ofthe die slide of the press arranged entirely between the front and backbeams of the crown-structure of the press and the toggle mechanisms fordriving the work clamping slide arranged on the outside of the front andback beam structure of the crown, said toggle mechanisms includingtoggle rocker shafts extending through the said crown beams and servingas supports for members of the gear train, and means connected to saidcrankshaft and to said rocker shafts for imparting a rocking movement tosaid rocker shafts to thereby actuate said toggle mechanisms.

6. A double action sheet metal press of the front to back gear andtoggle drive type having the gear train for driving the main crankshaftof the die slide of the press arranged entirely between the front andback beams of the crown structure of the press and having dual togglemechanisms for driving the work clamping slide arranged on the outsideof each of the front and back beam structures of the crown, said togglemechanisms including two parallel toggle rocker shafts extending throughthe said crown beams and serving as supports for members of the geartrain, and means including two more cranks, one at each end of the maincrankshaft for imbeam,

through said toggle Shafts.

parting rocking movement mechanisms to said rocker 7. In a sheet metalworking press of the double action front to back type, the combinationof a crown structure comprising a front and back beam, a main crankshaftjoumalled in said beams, a gear train disposed between said beams todrive the crankshaft, toggle mechanism disposed to the front and rear ofsaid beams respectively and adapted to operate the work clamping slideof the press, said toggle mechanisms including two rocker shaftsextending through said front and back beams of the crown structure, oneof said rocker shafts having rotatably mounted thereon an intermediategear driven from a pinion on the main drive shaft of furthermorerotatably mounted thereon a pinion for driving a second intermediategear. 7

8. In a sheet metal working press of the double action front to backtype, the combination of a crown structure comprising a front and back amain crankshaft journalled in said beams, a gear train disposed betweensaid beams to drive the crankshaft, toggle mechanism disposed to thefront and rear of said beams respectively and adapted to operate thework clamping slide of the press, said toggle mechanism including tworocker shafts extending through said front and back beams of the crownstructure, one of said rocker shafts having rotably mounted thereon anintermediate gear driven from a pinion on the main drive shaft of thepress, and having furthermore rotatably mounted thereon a pinion fordriving a second intermediate gear while the second" rocker shaft isadapted rotatably to carry a pair of pinions serving for the drive of apair of bull gears, said bull gears being mounted in driving connectionwith the cheeks of said main crankshaft.

9. In a sheet metal working press of the double action front to backtype, the combination of a crown structure comprising a front and a backbeam, a main crankshaft journalled in said beams, a gear train disposedbetween said beams to drive the crankshaft, toggle mechanism disposed tothe front and rear of said beams respectively and adapted to operate thework clamping slide of the press, said toggle mechanisms including tworocker shafts extending through said front and back beams of the crownstructure, one oil said rocker shafts having rotatably mounted thereonan intermediate gear driven from a pinion on the main drive shaft of thepress, and having furthermore rotatably mounted thereon a pinion fordriving a second intermediate gear, and means mounted on said crankshaftbut remote from the crank for imparting a rocking movement to saidrocker shafts.

110. In a sheet metal working press of the double action front to backtype, the combination of a crown structure comprising a front and a back:beam, a main crankshaft journalled in said beams, a gear train disposedbetween said beams to drive the crankshaft, toggle mechanism dis posedto the front and rear of said beams respectively and adapted to operatethe work clamping slide of the press, said toggle mechaintermediate gearwhile the second rocker shaft i adapted rotatably to carry a pair ofpinions serving for the drive of a pair of bull gears, said ,bull gearsbeing mounted in driving connection with said main crankshaft, and meansmounted on said crankshaft but remote from the crank for imparting arocking movement to said rocker shafts.

11. In a double action sheet metal press of the front to back gear andtoggle drive type the combination of a crown structure comprising afront ing toggle rocker shafts extending through the said crown beams,one of said rocker shafts having rotatably mounted thereon anintermediate gear driven from a pinion on the main drive shaft of thepress and having furthermore rotatably mounted thereon a pinion fordriving a second intermediate gear while the second rocker shaft isadapted rotatably to carry a :pair of pinions serving for the drive of apair of bull gears, said bull gears being mounted in driving connectionwith said main crankshaft, and means mounted on said crankshaft butremote from the crank for imparting a rocking movement to said rockershafts.

12. In a sheet metal working press of the double action type, a front toback rocker shaft arrangement extending through the crown of the 'pressand operatively connecting a toggle mechanism disposed at the front ofthe crown to a toggle mechanism disposed at the back of the crown and agear train drive for the die slide of the press disposed within thecrown with certain of the gear elements of said train rotatively mountedupon said rocker shaft arrangement.

13. In a sheet metal working press of the double action type, a front toback rocker shaft arrangement comprising two rocker shafts extendingthrough the crown of the press and operatively connecting a dual togglemechanism disposed at the front of the crown and a dual toggle mechanismdisposed at the back of the crown, said toggle mechanism serving todrive the work cl ping slide and a gear train drive for the die sli e ofthe press disposed within the crown with certain of the gear elements ofsaid train rotatively mounted upon said rocker shaft arrangement.

14. In a sheet metal working press of the double action type, a front toback rocker shaft arrangement comprising two shafts extending throughthe crown of the press and operatively connecting a dual togglemechanism disposed 0n the outside of the front of the crown and a. dualtoggle mechanism disposed on the outside of the back of the crown, saidtoggle mechanisms serving to drive the work clamping slide and a geartrain drive for the die slide of the press including the main crankshaftdisposed within the crown with certain of said gear elements rotativelymounted upon said rocker shaft arrangement and meansrnounted on saidcrankshaft for imparting a rocking movement through said togglemechanisms to said rocker shafts.

15. In a sheet metal working press of the double action type, a front toback rocker shaft arrangement comprising two shafts extending throughthe crown of the press and operatively connecting a dual togglemechanism disposed on the outside of the front of the crown and a dualtoggle mechanism disposed on the outside of the back of the crown, saidtoggle mechanisms serving to drive the work clamping slide and a geartrain drive for the die slide of the press including the main crankshaftdisposed within the crown with certain of said gear elements rotativelymounted upon said rocker shaft arrangement, and means including anauxiliary crankshaft mounted at each end of said main crankshaft forimparting a rocking movement to said rocker shafts.

16. In a sheet metal working press of the dollble action type, acrankshaft for operating the die slide of the press extending from frontto back of the press and disposed centrally between the sides of thepress, a pair of rocker shafts extending from front to back of the pressand having toggle mechanisms at their ends for driving the work clampingslide of the press, a gear train for driving said crankshaft, and meansdriven by said crankshaft for actuating said toggle mechanisms.

17. In a sheet metal press of the double action type, a crown structurehaving a front and a back beam, a crankshaft for operating the die slideof the press extending from front to rear of the press and disposedcentrally between the sides of the press, said crankshaft having aportion projecting forwardly of the front beam and a portion projectingrearwardly of the back beam, a pair of rocker shafts journalled in saidbeams and having iportions projecting forwardly of the front beam andrearwardly of the back beam, toggle mechanisms including levers mountedon said projecting portions of the rocker shafts for driving the workclamping slide of the press, means interconnecting said projectingportions of the crankshaft with said levers for rocking said shaftsthrough said levers, and a gear train disposed between the front andback beams for driving said crankshaft, said train including gearsrevolubly mounted on said rocker shafts.

FREDRICH J. RODE. MEREDITH R. HATCH.

